JP6673620B2 - Biological pressure-sensitive adhesive composition and biological pressure-sensitive adhesive sheet - Google Patents

Description

  The present invention relates to a biological pressure-sensitive adhesive composition and a biological pressure-sensitive adhesive sheet.

The pressure-sensitive adhesive sheet for a living body directly adhered to a living body represented by the skin is, for example, a bandage for the purpose of protecting or treating a wound, a patch called a transdermal absorption preparation for the purpose of treating or preventing various diseases, anti-inflammatory, It is widely used for various applications such as poultices, tapes, poultices for the purpose of analgesia, false nails, false eyelashes, false eyelashes, and wigs.
Such a pressure-sensitive adhesive sheet for a living body is widely used in a form in which various substrates represented by, for example, paper, nonwoven fabric, and various resins, and a pressure-sensitive adhesive layer forming a pressure-sensitive adhesive composition for a living body are laminated.

  Since it contains a large amount of water and suppresses rash to a living body, for example, and has an appropriate adhesive force with the living body, an emulsion-type (meth) acrylic copolymer is generally used in a pressure-sensitive adhesive composition for a living body. Including compositions are widely used.

  Bioadhesive compositions are widely known. For example, Patent Document 1 discloses an alkyl (meth) acrylate having 3 or less carbon atoms in an alkyl group, an alkyl (meth) acrylate having 4 or more carbon atoms in an alkyl group, a functional monomer, and another monomer. A medical pressure-sensitive adhesive composition containing an acrylic (co) polymer having a glass transition point of 10 ° C. or less, each containing a specific amount of a polymer and a polymer. According to Patent Literature 1, when the content of the alkyl (meth) acrylate having 4 or more carbon atoms in the alkyl group exceeds 30% by weight in the pressure-sensitive adhesive composition, the adhesive strength becomes too high and the exfoliation of the keratin is caused. Is supposed to happen.

JP-A-9-132525

There is a demand for a biological pressure-sensitive adhesive sheet to be attached to a living body for a longer time than before. For example, when a living body pressure-sensitive adhesive sheet is applied to a living body for 24 hours or more, sweating from the living body causes a decrease in the adhesive strength, and unintended peeling occurs. If the adhesive strength of the living body pressure-sensitive adhesive sheet is increased in order to suppress the peeling during the application, strong pain may be caused after use, that is, when the living body pressure-sensitive adhesive sheet is peeled from the living body.
That is, in a biological pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from a biological pressure-sensitive adhesive composition, it was difficult to peel off for a long time during application and to suppress pain at the time of peeling after use.

The present invention has been made in view of the above circumstances, and has as its object to achieve the following objects.
That is, an object of the present invention is to provide a living body having a pressure-sensitive adhesive composition derived from a biological pressure-sensitive adhesive composition and a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition, which does not peel for a long time during application and can suppress pain at the time of peeling after use. To provide a pressure-sensitive adhesive sheet.

Specific means for solving the problems include the following aspects.
[1] A structural unit (A) derived from a (meth) acrylic monomer having a solubility parameter of 9.5 or less is contained in an amount of 30% by mass or more and 65% by mass or less with respect to all the structural units, and the solubility parameter is 9.5 or less. Bioadhesive containing a (meth) acrylic polymer containing 35% by mass or more of structural units (B) derived from a (meth) acrylic monomer based on all the structural units and a surfactant, which exceeds 5 Agent composition.

[2] The biological pressure-sensitive adhesive composition according to [1], wherein the structural unit (A) is at least one of n-lauryl methacrylate and 2-ethylhexyl acrylate.

[3] The biological pressure-sensitive adhesive composition according to [1] or [2], wherein the structural unit (B) is at least one of methyl acrylate and methyl methacrylate.

[4] A biological pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition according to any one of [1] to [3].

  According to the present invention, a biological pressure-sensitive adhesive composition and a biological pressure-sensitive adhesive having a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition, which do not peel for a long time during application and can suppress pain at the time of peeling after use We can provide sheets.

  Hereinafter, specific embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and is implemented with appropriate modifications within the scope of the present invention. be able to.

In this specification, a numerical range indicated by using “to” means a range including numerical values described before and after “to” as a minimum value and a maximum value, respectively.
In the present specification, the amount of each component in the composition is, when a plurality of substances corresponding to each component are present in the composition, unless otherwise specified, the total amount of the plurality of substances present in the composition. Means

As used herein, “(meth) acrylate” is a term including both acrylate and methacrylate, and “(meth) acryl” is a term including both acryl and methacryl.
In the present specification, the “adhesive composition for living body” is also simply referred to as “adhesive composition” or “composition”.
In the present specification, the “biological pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition” is also simply referred to as “biological pressure-sensitive adhesive sheet” or “pressure-sensitive adhesive sheet”.
In the present specification, “(meth) acrylic monomer” is a monomer having at least one of an acryloyl group and a methacryloyl group.

[Body adhesive composition]
The pressure-sensitive adhesive composition for a living body of the present invention contains a structural unit (A) derived from a (meth) acrylic monomer having a solubility parameter of 9.5 or less in an amount of 30% by mass or more and 65% by mass or less based on all the structural units. A (meth) acrylic polymer (hereinafter, referred to as “methacrylic polymer” containing 35% by mass or more of a structural unit (B) derived from a (meth) acrylic monomer having a solubility parameter exceeding 9.5 with respect to all structural units. (Also referred to as “(meth) acrylic polymer” or “polymer”) and a surfactant.
The polymer is obtained by emulsion polymerization using, for example, a (meth) acrylic monomer, a surfactant, water and a polymerization initiator.
The pressure-sensitive adhesive composition for a living body of the present invention is generally used for a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from the pressure-sensitive adhesive composition for a living body. The details of the biological adhesive sheet will be described later.

The present inventor has described the reason why a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition of the present invention does not peel for a long time during application, and can suppress pain at the time of peeling after use. I think so.
In order to prevent the pressure-sensitive adhesive composition of the present invention from being peeled off even after sticking for a long time during the sticking and to suppress pain at the time of peeling after use, the pressure-sensitive adhesive composition has an affinity with a living body, It is necessary to suppress the absorption of water generated from living organisms.
The pressure-sensitive adhesive composition of the present invention contains a polymer containing 30% by mass or more and 65% by mass or less of structural units derived from a (meth) acrylic monomer having a solubility parameter of 9.5 or less. The adhesive composition due to moisture represented by perspiration at the time of application can suppress plasticization and swelling caused by excessive moisture absorption, decrease in adhesive strength, unintended peeling does not occur, and the adhesive force over time Excessive rise can be suppressed, and pain at the time of peeling can be suppressed. In addition, since the polymer contains a polymer containing 35% by mass or more of a structural unit derived from a (meth) acrylic monomer having a solubility parameter exceeding 9.5, affinity with a living body is improved, and the adhesive can be applied for a long time. Does not peel off. Therefore, the pressure-sensitive adhesive composition for living body of the present invention does not peel for a long time during application and can suppress pain at the time of peeling after use.

[(Meth) acrylic polymer]
The (meth) acrylic polymer contained in the pressure-sensitive adhesive composition of the present invention has a structural unit (A) derived from a (meth) acrylic monomer having a solubility parameter of 9.5 or less, and a solubility parameter of 9.5. And a structural unit (B) derived from a (meth) acrylic monomer in an amount exceeding a specific ratio. Therefore, the pressure-sensitive adhesive sheet of the present invention does not peel for a long time during application and can suppress pain at the time of peeling after use.

In the present invention, the dissolution parameter is a value calculated from Fedor's estimation formula. Specifically, the values of ΣEcoh and ΣV are calculated from the values of the cohesive energy density (Ecoh) and the molar volume (V) according to the structure, and are the values obtained by the following equations.
[Dissolution parameter] = [ΣEcoh / (ΣV × 4.182)] ^1/2

  The structural unit (A) derived from a (meth) acrylic monomer having a solubility parameter of 9.5 or less contained in the polymer includes, for example, n-lauryl methacrylate (solubility parameter 9.02), 2-ethylhexyl acrylate (same as above). 9.23) and n-butyl methacrylate (9.45). In particular, when the structural unit (A) is a structural unit derived from either n-lauryl methacrylate or 2-ethylhexyl acrylate, the glass transition temperature of the polymer becomes appropriately low, and thus the pressure-sensitive adhesive sheet of the present invention. Is preferable because it does not peel off even when applied to a living body for a long time.

  The structural unit (B) derived from a (meth) acrylic monomer having a solubility parameter of more than 9.5 contained in the polymer includes, for example, methyl acrylate (dissolution parameter 10.56) and ethyl acrylate (10.21). Propyl acrylate (9.96), n-butyl acrylate (9.77), methyl methacrylate (9.94), ethyl methacrylate (9.73), 2-hydroxyethyl acrylate (9.94) And acrylic acid (14.05) and methacrylic acid (12.54). In particular, if the structural unit (B) is a structural unit derived from either methyl acrylate or methyl methacrylate, the cohesive force will be moderate. Preferred.

  The polymer may be included as a structural unit derived from a monomer other than the monomer forming the structural unit (A) or the structural unit (B), as long as the excellent effects of the present invention are not impaired. Such monomers include, for example, vinyl formate, vinyl esters of saturated fatty acids represented by vinyl acetate, N-vinyl-2-propiolactam, N-vinyl-2-pyrrolidone, N-vinyl-2-piperidone, Examples thereof include vinyl lactams represented by N-vinyl-2-caprolactam and N-vinyl-2-heptolactam.

  The ratio of the sum of the masses of the structural units (A) and (B) to the weight of the polymer is preferably 90% or more, more preferably 95% or more, and even more preferably 100%. When the mass ratio is 90% or more, since the polymer contains more structural units derived from the (meth) acrylic monomer, the pressure-sensitive adhesive composition of the present invention has a more appropriate affinity for a living body. And the effect of not peeling for a long time is further exhibited.

The glass transition temperature of the polymer is preferably in the range of −60 ° C. to 10 ° C., and is preferably in the range of −50 ° C. to −−. A range of 20 ° C. is more preferred.
In the present invention, the term "flexibility" refers to a performance in which the adhesive sheet does not peel off when the adhesive sheet is attached to a site of a living body that bends, such as an elbow or a knee.

  The glass transition temperature in the present invention is a value obtained by converting the absolute temperature (K) of the polymer obtained by calculation of the following formula into a Celsius temperature (° C.).

In the formula, Tg1, Tg2,..., And Tgn are absolute values when each of monomer 1, monomer 2,. It is a glass transition temperature represented by a temperature (K). .., and mn are mass fractions of the respective monomers.
The “glass transition temperature represented by the absolute temperature (K) when a homopolymer is used” is represented by the absolute temperature (K) of a homopolymer produced by polymerizing the monomer alone. It refers to the glass transition temperature.
The glass transition temperature of the homopolymer was measured using a differential scanning calorimeter (DSC) (manufactured by Seiko Instruments Inc., EXSTAR6000) in a nitrogen gas stream, at a measurement sample of 10 mg, and at a heating rate of 10 ° C./min. The measurement was performed under the conditions, and the inflection point of the obtained DSC curve was defined as the glass transition temperature of the homopolymer.

The “glass transition temperature expressed by the Celsius temperature (° C.) of a homopolymer” of a typical monomer is −65 ° C. for n-lauryl methacrylate, −76 ° C. for 2-ethylhexyl acrylate, and n -Butyl methacrylate is 21C, n-butyl acrylate is -57C, methyl acrylate is 5C, ethyl acrylate is -27C, methyl methacrylate is 103C, and acrylic acid is 163C. It is.
For example, by including a structural unit derived from these typical monomers, the above-mentioned glass transition temperature of the polymer can be appropriately adjusted.

[Surfactant]
The pressure-sensitive adhesive composition of the present invention contains a surfactant. The surfactant contained in the pressure-sensitive adhesive composition of the present invention has a hydrophobic group and a hydrophilic group in the same molecule.

  The surfactant contained in the pressure-sensitive adhesive composition of the present invention is not particularly limited, and various surfactants generally used for emulsion polymerization, such as nonionic surfactants, anionic surfactants, and cationic surfactants Surfactants and amphoteric surfactants can be used. These surfactants can be used alone or in combination of two or more.

  More specifically, examples of the nonionic surfactants include polyoxyethylene lauryl ether, polyoxyethylene alkyl ethers represented by polyoxyethylene stearyl ether, polyoxyethylene octyl phenyl ether, and polyoxyethylene nonyl phenyl ether. Polyoxyethylene alkyl phenyl ethers, sorbitan monolaurate, sorbitan monostearate, sorbitan higher fatty acid esters such as sorbitan trioleate, and polyoxyethylene sorbitan higher such as polyoxyethylene sorbitan monolaurate Fatty acid esters, polyoxyethylene monolaurate, polyoxyethylene higher fatty acid esters represented by polyoxyethylene monostearate, Maleic acid monoglyceride, glycerin higher fatty acid esters typified by stearic acid monoglyceride, polyoxyethylene polyoxypropylene block copolymers.

  Examples of the anionic surfactants include higher fatty acid salts represented by sodium oleate, for example, alkylaryl sulfonates represented by sodium dodecylbenzenesulfonate, and alkyl sulfates represented by sodium lauryl sulfate Salts, polyoxyethylene alkyl ether sulfates represented by sodium polyoxyethylene lauryl ether sulfate, polyoxyethylene alkyl aryl ether sulfates represented by sodium polyoxyethylene nonylphenyl ether sulfate, sodium monooctyl sulfosuccinate, Alkyl sulfosuccinates represented by sodium dioctyl sulfosuccinate and sodium polyoxyethylene lauryl sulfosuccinate

  Examples of the cationic surfactants include alkylamine salts represented by laurylamine acetate, quaternary ammonium salts represented by lauryltrimethylammonium chloride and alkylbenzyldimethylammonium chloride, and polyoxyethylalkylamine. .

  Examples of the amphoteric surfactants include, for example, alkyl betaines represented by lauryl betaine.

  Further, a so-called reactive surfactant having a copolymerizable unsaturated group in the molecular structure can also be suitably used.

  Since the surfactant contained in the pressure-sensitive adhesive composition of the present invention has a sufficient track record in a pressure-sensitive adhesive composition for living body, the number of moles of acid number ethylene added is in the range of 10 mol to 100 mol, preferably in the range of 20 mol to 70 mol. Is preferred.

  In addition, as such a surfactant, polyoxyethylene nonyl phenyl ether manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name Neugen EM-230D, Neugen EM-250, trade name BLAUNON N-520, trade name, manufactured by Aoki Yushi Kogyo Co., Ltd. N-550, manufactured by NOF Corporation Nonion NS-230 and NS-270 are commercially available.

  The total amount of the surfactant contained in the pressure-sensitive adhesive composition of the present invention is, for example, in the range of 1 part by mass to 10 parts by mass, preferably in the range of 3 parts by mass to 5 parts by mass with respect to 100 parts by mass of the polymer in total. It is.

[Other additives]
The polymer contained in the pressure-sensitive adhesive composition of the present invention can be prepared using a polymerization initiator.
Examples of the polymerization initiator include persulfates represented by potassium persulfate, sodium bisulfite, and ammonium persulfate, and azo compounds represented by azobisisobutyronitrile.
The total amount of the polymerization initiator used at the time of preparing the polymer is, for example, in the range of 0.01 to 5 parts by mass, preferably 0.1 to 1 part by mass with respect to 100 parts by mass of the total amount of the polymer. Range.

  The polymer may contain a chain transfer agent as long as the excellent effects of the present invention are not impaired. Examples of such a chain transfer agent include mercaptan compounds represented by alkyl mercaptan, thioglycol, and 2-mercaptopropionic acid.

  The pressure-sensitive adhesive composition of the present invention may contain various pigments, various dyes, tackifiers, and inorganic fillers as long as the excellent effects of the present invention are not impaired. Further, various resins and oligomers other than the (meth) acrylic polymer may be included.

  The pressure-sensitive adhesive composition of the present invention can be applied to so-called transdermal absorption preparations by containing various drugs. Such various drugs include, for example, coronary vasodilators, antiarrhythmic agents, angina pectoris, antihypertensives, inotropics, bronchial asthmatics (bronchodilators), antihypertensives, calcium antagonists, anti-inflammatory analgesics, skin Disease agents, local anesthetics, antihypertensive diuretics, hypnotics and sedatives, central nervous system drugs, psychoactive drugs, hormonal drugs, sulfa drugs, antituberculosis drugs, antihistamine drugs, antiallergic drugs, and analgesics.

[Adhesive sheet for living body]
The biological pressure-sensitive adhesive sheet of the present invention has a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition. More specifically, the biological pressure-sensitive adhesive sheet of the present invention is obtained by applying a biological pressure-sensitive adhesive composition to, for example, release paper and then drying it to form a pressure-sensitive adhesive layer. Then, paper, a nonwoven fabric, and various substrates represented by various resins This is an embodiment in which the layers are stacked.

Examples of embodiments of the pressure-sensitive adhesive sheet of the present invention include bandages, dressings, and drapes.
Further, another embodiment of the pressure-sensitive adhesive sheet of the present invention is a patch, a poultice, a tape, or a poultice called a transdermal absorption preparation.
Further, another embodiment of the pressure-sensitive adhesive sheet of the present invention includes false nails, false eyelashes, false eyelashes, wigs, body seals and tattoo seals that are temporarily attached to the human body, and lift-up tapes that make face wrinkles and sagging less noticeable. , Eye tape for double eyelid correction, face mask for face pack.
Another embodiment of the pressure-sensitive adhesive sheet of the present invention is an electrode (biological electrode) provided in a medical device used for various treatments and tests.
Furthermore, the pressure-sensitive adhesive sheet of the present invention can be applied not only to the human body but also to pet animals such as dogs, cats, and rabbits.

  When the pressure-sensitive adhesive sheet of the present invention is peeled from a living body, there is no remaining part of the pressure-sensitive adhesive composition on the living body, that is, no so-called adhesive residue. In general, when adhesive residue is generated when a biological pressure-sensitive adhesive sheet is used, an operation of separately wiping the adhesive after peeling is required, which is a problem.

  Hereinafter, the present invention will be described more specifically with reference to examples. The present invention is not limited to the following examples as long as the gist is not exceeded.

[Example 1]
30 parts by mass of deionized water was charged into a reaction vessel equipped with a thermometer, a stirrer, and a reflux condenser, and the internal temperature was raised to 70 ° C. On the other hand, in another reaction vessel, 20 parts by mass of ion-exchanged water, and polyoxyethylene nonylphenyl ether (trade name: Neugen EM-230D, manufactured by Daiichi Kogyo Seiyaku Co., Ltd .; active ingredient concentration: 70% by mass) as a surfactant, 5.7 Parts by mass (active ingredient: 4 parts by mass) were charged and dissolved by stirring, and then 30 parts by mass of 2 ethylhexyl acrylate (2EHA), a (meth) acrylic monomer having a dissolution parameter of 9.5 or less, A monomer mixture consisting of 68 parts by mass of methyl acrylate (MA), which is a (meth) acrylic monomer having a dissolution parameter exceeding 9.5, and 2 parts by mass of acrylic acid (AA) is added, and the mixture is stirred. A premix was obtained. The contents of the reaction vessel were heated while stirring under a nitrogen stream, and when the water temperature in the reaction vessel reached 70 ° C., 0.03 parts by mass of sodium bisulfite was added. 20 parts by mass of an aqueous potassium sulfate solution (active ingredient: 0.4 parts by mass) and a monomer premix were sequentially added to initiate polymerization, and a polymerization reaction was carried out for about 5 hours. After the completion of the polymerization reaction, stirring was continued at the same temperature for about 2 hours, followed by cooling to obtain the composition of Example 1.
The pH of the obtained composition was 2.4, the viscosity (BH type, measured at 20 rpm, 25 ° C.) was 257 mPa · s, the solid content was 59.1%, and the glass transition temperature was − 24 ° C.

[Examples 2 to 12, Comparative Examples 1 to 6]
Except that the compositions described in Table 1 were used, each composition was obtained in the same procedure as in Example 1.
In Table 1, each numerical value in the composition represents parts by mass, and the numerical value in parentheses after the name of the (meth) acrylic monomer represents a dissolution parameter.
In Table 1, “LMA” is n-lauryl methacrylate, “2EHA” is 2-ethylhexyl acrylate, “BMA” is n-butyl methacrylate, “BA” is n-butyl acrylate, and “MA” is “EA” is an abbreviation for ethyl acrylate, “MMA” is for methyl methacrylate, and “AA” is for acrylic acid.
In Table 1, "EM-230D" is a product of Daiichi Kogyo Seiyaku Co., Ltd. under the brand name Neugen EM-230D, "EM-250" is a brand name of Neugen EM-250, and "NS-270" is NOF Corporation These are the abbreviations of Nonion NS-270, a product name manufactured by the company. In the case of surfactants which are commercially available after being diluted, the parts by mass after conversion into active ingredients are described.
Further, in Table 1, "-" means that the corresponding component was not blended.

[Evaluation]
Each of the pressure-sensitive adhesive compositions of Examples and Comparative Examples was evaluated for each item of retention, pain, adhesive residue, and flexibility. Table 1 shows the results.

The test piece used for each evaluation was produced by the following procedure.
The respective pressure-sensitive adhesive compositions of Examples and Comparative Examples were coated on release paper (trade name: G7B-J, manufactured by Oji Tack Co., Ltd.) so that the mass after drying would be in the range of 70 to 90 g / m ^2. After heating and drying at 100 ° C. for 10 minutes, the sample was bonded to a nonwoven fabric (trade name: Oikos AP20600400, manufactured by Nisshinbo Holdings Inc.), and a test piece as a biological pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from a biological pressure-sensitive adhesive composition was added did. The size of the test piece is 5 cm square. The following items were evaluated using this test piece.

1. Retention The test specimen prepared as described above was retained for 24 hours after attaching it to human skin, and the presence or absence of peeling was visually checked. Evaluation was made according to the following criteria.
A: No peeling.
：: There is some peeling at the end, but there is no practical problem.
×: peels off.

2. Pain retention was evaluated together with the evaluation. The specimen was held for 24 hours after application to human skin, and then the test piece was rapidly peeled off by hand. The degree of pain was evaluated according to the following criteria.
A: No pain at the time of peeling.
：: There is some pain at the time of peeling, but there is no practical problem.
×: Pain is strongly felt during peeling.

3. Residue of glue The test piece prepared above was adhered to human skin for 24 hours and then peeled off by hand. Next, the presence or absence of glue residue on the skin was visually checked, and evaluated according to the following criteria.
：: No adhesive residue after peeling.
：: There is some adhesive residue, but there is no practical problem.
X: Adhesive residue is remarkable and there is a problem.

4. Flexibility After the test piece prepared above was attached to an elbow bent at 90 degrees, bending and stretching were immediately repeated 10 times. The presence or absence of peeling of the test piece was evaluated according to the following criteria.
A: No peeling.
：: There is some peeling at the end but no problem.
×: Peeling occurs.

  As shown in Table 1, the test piece provided with the pressure-sensitive adhesive composition of each example passed all the evaluation items. On the other hand, the test piece provided with the pressure-sensitive adhesive composition of each comparative example was defective in any of the evaluation items. For example, the test piece provided with the pressure-sensitive adhesive composition of Comparative Example 1 has passed the evaluation of the retention property, but has a problem of causing pain when peeled from the skin.

  The pressure-sensitive adhesive compositions for living bodies of Examples 1 to 12 each include a polymer composed of only a structural unit derived from a (meth) acrylic monomer. That is, in the polymers contained in the biological pressure-sensitive adhesive compositions of Examples 1 to 12, the ratio of the sum of the weights of the structural units (A) and (B) to the weight of the polymer is 100%. .

  As described above, the biological pressure-sensitive adhesive sheet having the pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition of the present invention does not peel for a long time during application and can suppress pain at the time of peeling after use.

Claims (3)

A structural unit (A) derived from a (meth) acrylic monomer having a solubility parameter of 9.5 or less is contained in an amount of 30% by mass or more and 65% by mass or less with respect to all the structural units, and the solubility parameter exceeds 9.5. The (meth) acrylic polymer containing 35% by mass or more of the structural unit (B) derived from the (meth) acrylic monomer based on all the structural units, and the addition mole number of the acid value ethylene is in a range of 10 mol to 100 mol. Containing polyoxyethylene nonyl phenyl ether ,
The structural unit (B) contains at least one of methyl acrylate and methyl methacrylate,
A pressure-sensitive adhesive composition for living body, wherein the total amount of the surfactant is 3 parts by mass to 5 parts by mass based on 100 parts by mass of the total of the (meth) acrylic polymer . The pressure-sensitive adhesive composition for living body according to claim 1, wherein the structural unit (A) is at least one of n-lauryl methacrylate and 2-ethylhexyl acrylate. A biological pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer derived from the biological pressure-sensitive adhesive composition according to claim 1 .